Most people never consider the amount of research and testing that goes into everyday items like cosmetics. From researching and developing new shades and colors, all the way to safety testing, the cosmetics industry is a state-of-the-art sector that relies on a variety of methods to ensure its products are safe. Here’s how one team of engineers seeks to reduce animal testing in the market through the introduction of 3D-printed living skin.
Why Animal Testing Is Still Used in the Cosmetics Industry
In the past, animal testing was the primary way in which cosmetics or medical researchers could test their products on living creatures. In the early days, these tests were as simple as placing the product on the animal and monitoring behavior.
Over the last century, animal testing has seen a drastic boost in capabilities. Researchers can grow human organs and other essential body parts on other living creatures to improve testing accuracy.
Additionally, advanced computer modeling allows for simulation tests. This approach is more affordable, faster, and accurate than animal testing in most scenarios. However, despite these advancements, there are still many cosmetic and medical firms that rely on animal testing of their products.
The Ethical and Scientific Problems with Animal Testing
There are some obvious ethical issues with animal testing. For one, there has been a long history of mistreatment and cruelty towards these test subjects. These concerns hit a fevered pitch in 2010.
That’s when the EU introduced a host of animal testing restrictions with the overall goal to phase the practice out in the coming years. Thankfully, a team of innovative engineers may have come up with a viable solution.
How 3D-Printed Skin Could Replace Animal Testing in Labs
The study “Protocol for the fabrication of self-standing (nano)cellulose-based 3D scaffolds for tissue engineering“1 delves into a new 3D printing method that combines customized ink with proprietary printing technology to create living imitation skin.
This artificially grown skin will allow engineers in the future to conduct in vitro tests, such as measuring absorption and toxicity of nanoparticles from cosmetics and medications, without using any animal subjects.
Using 3D Scaffolds to Grow Human Skin Cells for Testing
Researchers from Graz University of Technology (TU Graz) and the Vellore Institute of Technology (VIT) in India utilize a proprietary 3D printer and components to create porous scaffolds made from nanocellulosic materials. These 3D scaffolds are now a critical component of the testing industry.
What Makes 3D-Printed Skin a Viable Testing Platform
3D scaffolding has some distinct advantages over alternatives when discussing animal testing. For one, no animals are hurt. Additionally, it can accurately mimic the extracellular matrix (ECM). This capability allows engineers to grow a variety of cells, which will mature as if they were inside the body, allowing engineers to test their products and treatments effectively.
Unlike other cell growth methods, 3D scaffolding provides structural support and customization. For example, 3D scaffolding engineers can customize pore structures, biocompatibility, and other key details such as the ability to support mammalian cell adhesion and proliferation.
The team decided to use plant-based resources as part of their approach. They knew they wanted to achieve high mechanical strength and an extensive surface at a nanoscale. After much research, they determined that the combination of nanofibrillated cellulose (NFC), carboxymethyl cellulose (CMC), and citric acid (CA)would offer the synergistic approach they desired.
3D Printer and Tools Used to Create Synthetic Skin Scaffolds
Specifically, the team selected a BioScaffolder 3.1 3D printer with a customized print nozzle. The engineers then programmed crucial details like pressure and strand distance using GeSiM Robotics BS3.1/3.2 software. This arrangement had the dispensing pressure set to a 220 kPa–260 kPa range with a strand distance of 500 μm–900 μm and a strand height of 0.2 mm.
The scientist selected a printing speed of 15 mm/s and a Z-offset of 0.0 mm. This strategy worked well with the hydrogel’s high water content. This high water content also makes an ideal environment for cell growth, but it does complicate printing.
To combat the added hydration, engineers created a cellulose derivative with carboxyl groups. This chemical improved water retention and adhesion. It also improved water retention, cross-linking, interfacial adhesion, and ionic cross-linking capacity, making it an ideal additive for tissue engineering constructs. Notably, the citric acid acts as a natural crosslinker and covalent bonding enhancer that helps stabilize the scaffold structure while maintaining biocompatibility.
Freeze-Drying Process for Stabilizing 3D-Printed Scaffolds
Freeze drying was another method used to remove unwanted hydration in he hydrogel. This method is ideal because it removes excess water while maintaining the porous structure intact. The sudden temperature drop also boosts crosslinking of carboxylic and hydroxyl groups.
Source – Manisha Sonthalia – Vellore Institute of Technology
Nanocellulose-Based Bio-Ink: Composition and Role in Bioprinting
Part of the new 3D printing approach relies on the use of nanocellulose ink. This ink combines nanofibrillated cellulose (NFC), carboxymethyl cellulose (CMC), and citric acid (CA). The citric acid acts as a final bonding agent in the solution. Notably, the engineers created 4 ink variations for testing.
How 3D-Printed Scaffolds Mimic Real Human Skin
The 3D-printed structure made of optimised hydrogel shared many similarities with human skin. For example, it had the same 3-layer structure and living cell types. However, the initiation skin can be created to mimic a wide variety of skin types and ailments with living cells. It also has the same biomechanics as human skin.
Hydrogels in Tissue Engineering: Supporting Cell Growth
The team started with the creation of a special hydrogel, capable of interacting with and cultivating living cell growth. The team tested several mixtures until they found one that demonstrated improved mechanical stability and resistance to hydrolytic degradation.
Bioprinting Living Cells for Cosmetic and Medical Testing
The engineers noted that the 3D printing of living cells could grow, mature, and survive in the hydrogel solution for 3 weeks while developing the living skin tissue. The team achieved living cell growth using cross-linking methods for stabilization. Notably, there was no need to utilize dangerous cytotoxic chemicals. Additionally, there were reduced post-processing tasks.
How Scaffolds Are Neutralized for Safe Cell Culturing
The engineers took the 3D scaffolding, coated it with sodium hydroxide, and then rinsed it thoroughly. This step was crucial to guarantee that all residual alkali was removed. This step also requires a 60-minute soak to ensure full neutrality.
Testing the Viability of 3D-Printed Skin Structures
The engineers conducted several tests to ensure the cells they printed matured and were accurate. The team examined cell growth and maturity as the first step. Specifically, they were keen to determine if the cells were exactly like those found in the body or if there were detailed differences that would make utilizing them for testing obsolete.
Mechanical Stability and Biocompatibility of 3D-Printed Skin
The testing proved the structure is resilient and extremely stable, thanks to the proprietary hydrogel used. The key takeaways of the new printing method are that the cross-linked materials are non-cytotoxic and mechanically stable.
Additionally, it was determined that lower temperatures and shorter or longer crosslinking times affect the crosslinking process. TU Graz researchers took note that they could reduce the crosslink rate to achieve changes in the physicochemical properties of the scaffold
Benefits of 3D-Printed Skin in Reducing Animal Testing
There are several benefits that this study brings to the market. For one, it is easy to envision animal testing becoming obsolete. There’s no reason to test on animals when a more affordable and effective method exists. Additionally, this data should help firms make the transition from animal testing to the use of lab-grown 3D printing living cells.
When Will 3D-Printed Skin Be Used in Cosmetic Testing?
There are many applications of this technology that could help save both human and animal lives. The obvious application for this tech is in the cosmetic and medical testing fields. The use of 3D-printed skin will make animal testing a less attractive option in the future.
This customizable skin can be made to replicate a wide variety of human skin types and locations. As such, it will provide the ideal testing solution for researchers seeking to monitor the effects of their products on the body. In this way, this data offers a glimpse into the framework for developing versatile and sustainable biomaterials for regenerative medicine.
Bioprinting in Space: Future Use Cases for Human Health
Another use case for these advanced human cell growth projects is helping expand the reach of interstellar explorers. In the future, space exploration will require humans to travel from Earth and probably never return.
As part of their survival strategy, they will need to be able to provide adequate healthcare millions of miles from home. The use of a 3D printer is seen as the best solution to this problem. Astronauts of the future could rely on 3D-printed organs, skin, and other body components to endure until they can finish their mission.
The use of 3D printing skin for testing could begin within the next 3-5 years, as there’s strong demand for this tech. However, the goal to print full organs is still 10-20 years out, as both scientific, medical, and legal aspects of the technology need to be aligned.
The Scientists Behind the 3D-Printed Skin Breakthrough
This study was led by a team of innovative researchers from Graz University of Technology (TU Graz) and the Vellore Institute of Technology (VIT) in India. Specifically, the article lists Tamilselvan Mohan, Matej Bračič, Doris Bračič, Florian Lackner, Chandran Nagaraj, Andreja Dobaj Štiglic, Rupert Kargl, Karin, and Stana Kleinschek as contributing to the work.
What’s Next for 3D-Printed Skin in Medical and Cosmetic Testing
Now, the team will set its focus on optimizing its hydrogel and ink design to make it faster, more reliable, and affordable. They will also try different mixtures and approaches to find the optimal balance between costs, printability, structural integrity, and biological performance.
A Public Company Advancing Bioprinting Technology
There are several companies involved in the bioprinting sector. These firms have a variety of tasks, from offering support in the form of software for developing advanced 3D print layouts, to hardware and printer manufacturers. Each of these companies serves a vital role in the market. Here’s one firm set to remain a top performer for the foreseeable future.
Few companies have the influence and reputation in the bioprinting sector as 3D Systems (DDD +7.41%). This firm first pivoted towards the bioprinting sector in 2017 after joining forces with another market leader, United Therapeutics. Since that time, it has played a critical position in providing crucial components to the market, including bioinks and other hardware.
Today, 3D systems play a crucial role in the drug discovery and research sectors. It’s regarded as one of the largest pure-play 3D printing companies by revenue and market cap. Additionally, the company continues to make acquisitions to drive market positioning. Specifically, it acquired the bioprinting firm Allevi, furnishing its technical capabilities.
3D Systems Corporation (DDD +7.41%)
Those seeking a reliable and proven bioprinting stock should do more research into 3D systems. The company has secured a reputation as an innovator and has a large network of partners and investors that support its research, including the company’s goal to one day grow complete human organs. While this goal may still be some years away, this research will undoubtedly help speed things up.
Latest on 3D Systems
3D Printed Living Skin – Healing Meets Tech
You have to commend TU Graz and the Vellore Institute of Technology in India for developing their 3D-printed skin. This upgraded method could help usher in an age of zero animal testing and more effective drugs. For now, this study should be seen as a ray of hope for animal activists, medical professionals, and the entire cosmetic industry.
Learn about other cool Biotech breakthroughs here.
Studies Referenced:
1. Mohan, T., Bračič, M., Bračič, D., Lackner, F., Nagaraj, C., Dobaj Štiglic, A., Kargl, R., & Stana Kleinschek, K. (2025). Protocol for the fabrication of self-standing (nano)cellulose-based 3D scaffolds for tissue engineering. STAR Protocols, 6(2), 103583. https://doi.org/10.1016/j.xpro.2024.103583